Noise balance pre-reconstruction data decomposition in spectral CT

Patent metadata

Field	Value
Publication number	US-8965095-B2
Application number	US-201313906110-A
Country	US
Kind code	B2
Filing date	May 30, 2013
Priority date	May 30, 2013
Publication date	Feb 24, 2015
Grant date	Feb 24, 2015

Abstract

More than two acquired energy or spectral M bins are used for photon counting detectors in a CT system. In the pre-reconstruction data decomposition, the measured photo counts in the M acquired spectral bines are combined into a predetermined fewer number of processed or weighted spectral bines N, which is at least two in number and represents a number of selected basic materials. Since the N basis materials are selected in the imaged subject where N<M, the noise is balanced in the pre-reconstruction data decomposition. In some more detail, after the photon counts n(E) is acquired in each of the M spectral bins as indicated by E=1 to M at each of the detector units for every view, the M acquired spectral bins is combined into the N processed spectral bins so that the photon counts in the N processed spectral bins are substantially balanced to have a least number of differences among the N processed spectral bins. Subsequently, the substantially balanced photon counts in each of the processed spectral bins are related to the material thickness L(i), where i=1 to M. Using a coordinate pursuit technique, the non-zero L(i) is found. The above is repeated for each of the detector units and for all views before reconstructing images based upon the non-zero thickness.

First claim

What is claimed is:

1. A method of noise balancing in spectral data, comprising:
acquiring from a subject spectral data including a first set of photon counts in a first number of at least three acquired spectral bins according to fixed thresholds for a predetermined number of views each having a family of ray-sums;
combining the first set of the photon counts in the acquired spectral bins into a second set of photon counts in a second number of two or more processed spectral bi…

Assignees

• Toshiba Kk
• Toshiba Medical Sys Corp

Inventors

• Zou Yu
• Wang Xiaolan

Classifications

• G06T12/10

  Physics · mapped topic

• G06T7/0012 Primary

  Physics · mapped topic

• A61B6/5258 Primary

  Human Necessities · mapped topic

• G06T2211/408

  Physics · mapped topic